The present invention relates to hole closure devices for blood vessels.
Many medical procedures require forming holes in blood vessels. After the procedure is completed, the holes must be closed, to prevent a fatal hemorrhage. Typically, such holes are closed using sutures, or by applying pressure against the hole.
U.S. Pat. No. 5,938,425 to Janzen et al., the disclosure of which is incorporated herein by reference, suggests sealing a hole by providing a sealing material outside of the hole.
U.S. Pat. No. 5,964,782 to Lafontaine et al., the disclosure of which is incorporated herein by reference, describes a catheter having hooks at its ends for bringing the sides of a hole together, for sealing by pressure or by electro-coagulation.
It is an object of some preferred embodiments of the invention to provide an implanted device for sealing holes in a blood vessel, the device having a smaller chance of retraction of spikes, barbs or other tissue engagement elements of the device, from the blood vessel, than devices of the prior art.
An aspect of some preferred embodiments of the invention relates to mechanically decoupling the spikes of a hole closure device from a part of the device that controls the device general geometry. Thus, the deformation of the spikes does not affect the device geometry and vice-versa. In a preferred embodiment of the invention, this results in a separation between the forces that change the device geometry to close the hole and the forces that maintain the spikes in side the blood vessel. This separation is expected to prevent the geometric distortion of the device from inadvertently retracting the spikes form the blood vessel.
In a preferred embodiment of the invention, the decoupling is achieved by assuring that energy stored by the device for closing the hole in the blood vessel is not stored in the spikes or in structures that spring-load the spikes. Thus, release of the energy is less likely to affect the hold of the spikes on the vessels. In plastically deformed devices, the spikes are configured so that the plastic deformation does not affect the spikes or parts of the device that spring-load the spikes.
An aspect of some preferred embodiments of the invention relates to providing a pivot bar for vessel-engaging spikes of a hole closure device. Preferably, the pivot bar is not part of the load bearing structure of the device. A potential advantage of using a pivot bar is that a spike can be rotated around the pivot bar without bending the spike and without and protrusion from the plane of the device and/or the surface of the blood vessel. Preferably, the pivot bar defines at its ends or along its length hinges (or weakened points) for controlling the twisting of the bar relative to the rest of the device, however, this is not necessary.
An aspect of some preferred embodiments of the invention relates to spacing the spike used to engage the blood vessel away from a hole in the blood vessel. Preferably, this results in a lower probability of the spike inadvertently retracting from the blood vessel.
An aspect of some preferred embodiments of the invention relates to a hole-closure device design, in which two concentric structures are provided, an inner structure for controlling the device geometry and an outer structure for supporting spikes and/or other means of engaging the blood vessel. Optionally, the spikes are coupled to the inner structure only through tab means provided to bend the spikes out of plane.
An aspect of some preferred embodiments of the invention relates to providing a hinge in a hole closure device. In a preferred embodiment of the invention, when the device distorts to close a hole, the distortion is controlled by the hinge, for example, being focused at the hinge or being prevented at the hinge. Preferably, the hinge is integral with the device. Alternatively, the device is formed of two or more parts attached to each other by the hinge. In a preferred embodiment of the invention, the device is designed for sealing an elongate cut in a blood vessel, by deforming between a substantially round configuration to a substantially ellipsoid configuration.
In a preferred embodiment of the invention, a multiple part device is provided, with all of the multiple parts being outside of the blood vessel and, preferably, being substantially equivalent in function.
An aspect of some preferred embodiments of the invention relates to a bi-stable hole closure device. In a preferred embodiment of the invention, the device has at least two stable states, a first state in which the device defines an open lumen through which a catheter, cannula or other tube may be provided and a second state in which the lumen is significantly contracted or even closed.
An aspect of some preferred embodiments of the invention relates to an elastic clip for closing a hole in a blood vessel. In a preferred embodiment of the invention, the clip is maintained in an open configuration, suitable for engaging a blood vessel, by inserting a spacer in the clip. After engaging the blood vessel, the spacer is moved or removed, so the clip can close. Preferably, the closure is elastic, super elastic or shape-memory based. Alternatively, the closure may be plastic, as a result of the application of force.
There is thus provided in accordance with a preferred embodiment of the invention, a hole closure device, comprising:
at least two blood vessel engaging structures, each comprising a base;
at least one second, deformable, structure, coupled to said at least two blood-vessel engaging structures and having a first deformation state and a second deformation state, wherein said at least one second deformable structure urges said two blood vessel engaging structures towards each other when going from said first deformation state to said second deformation state,
wherein, said change in deformation state is at least partially mechanically decoupled from each of said blood-vessel engaging structures, such that it does not effect a substantial deformation of said blood-vessel engaging structure relative to said base.
Preferably, said at least one second deformable structure comprises a deformable ring-like structure, adapted to enclose a blood vessel cannula-like tube in said first deformation state. Preferably, the device comprises a ring-like element on which said at least one deformable structure is mounted and wherein said at least one second deformable structure comprises at least two bending elements that couple said blood-vessel engaging structures to said ring-like element. Preferably, said ring-like element defines a lumen that has a substantially same radius in said deformation states. Alternatively, said blood vessel engaging structures each comprise at least one spike adapted for insertion into a wall of a blood vessel.
In a preferred embodiment of the invention, said blood vessel engaging structures each comprise at least two spikes adapted for insertion into a wall of a blood vessel. Preferably, said blood vessel engaging structures each comprise a pivot bar on which said spike is mounted.
In a preferred embodiment of the invention, said blood vessel engaging structures each comprise at least one tab, mounted on said pivot bar. Preferably, said tab comprises an anchor for holding said tab. Alternatively or additionally, said pivot bar comprises a hinge at either end.
In a preferred embodiment of the invention, said pivot bar is straight. Alternatively or additionally, said pivot bar is mounted on a spacer that spaces said pivot bar from said at least one second deformable structure.
In a preferred embodiment of the invention, said base is adapted for abutment against the blood vessel. Preferably, said bases are spaced apart a distance sufficient to prevent eversion of a blood vessel in which a hole is closed. Alternatively, said bases are spaced apart a distance sufficient to cause at least partial eversion of a blood vessel in which a hole is closed.
In a preferred embodiment of the invention, said at least one second deformable structure comprises at least two deformable structures connected by at least one joint. Preferably, said joint is elastic. Alternatively or additionally, said joint comprises a segment of a circle.
Alternatively, said joint is free turning for at least a range of angles.
In a preferred embodiment of the invention, said joint is integral with said at least two deformable structures.
In a preferred embodiment of the invention, said joint is formed by an interlocking of the two deformable structures.
In a preferred embodiment of the invention, said at least one deformable structure comprises a bar.
In a preferred embodiment of the invention, at least one of said blood vessel engaging structures is radially external to said at least one deformable structure. Alternatively or additionally, at least one of said blood vessel engaging structures is radially internal to said at least one deformable structure.
There is also provided in accordance with a preferred embodiment of the invention, a hole closure device, comprising:
at least one pivot bar;
at least one spike mounted on said spike such that rotating said spike around said bar twists said pivot bar; and
a base to which said at least one bar is coupled and which base does not encompass said bar. Preferably, the device comprises at least one structure which supports said pivot bar and which couples said pivot bar to said base.
Alternatively or additionally, said base comprises a deformable ring-like element. Preferably, said base comprises at least two hinges at opposite ends of said base.
There is also provided in accordance with a preferred embodiment of the invention, a hole closure device, comprising:
a deformable ring-like structure;
a plurality of spikes coupled to said structure, each of said spike comprising a base; and
a coupling structure coupling said base to said ring-like structure, wherein said base is radially spaced from said ring-like structure by said coupling structure, at least the length of said spike. Preferably, said spikes are each mounted on a pivot bar.
There is also provided in accordance with a preferred embodiment of the invention, a hole closure device comprising:
a first body part comprising:
a plurality of blood-vessel engaging structures, adapted to remain outside a blood vessel; and
at least a first hinge part coupled to said plurality of blood vessel engaging structures; and
a second body part comprising:
a plurality of blood-vessel engaging structures adapted to remain outside a blood vessel; and
at least a second hinge part coupled to said plurality of blood vessel engaging structures,
wherein said first and said second hinge parts are adapted to interlock to form a hinge.
There is also provided in accordance with a preferred embodiment of the invention, a blood vessel clip, comprising:
at least two spikes;
at least one tab, perpendicular to at least one of said spikes; and
an elastic body connecting the two spikes, said body having a greater inner dimension away from said spike than nearer said spike.
There is also provided in accordance with a preferred embodiment of the invention, a bi-stable hole closure device, comprising:
at least two arms, coupled to each other at either end thereof, wherein:
a first one of said arms is less flexible than a second one of said arms, and wherein said second arm is adapted to have two stable states, one state in which the second arm is spaced from said first arm and one state in which said second arm is adjacent said first arm; and
a plurality of blood-vessel engaging elements mounted on each of said arms.